diff options
Diffstat (limited to 'other-licenses/7zstub/src/CS/7zip/Compress/LZ/LzBinTree.cs')
| -rw-r--r-- | other-licenses/7zstub/src/CS/7zip/Compress/LZ/LzBinTree.cs | 367 |
1 files changed, 367 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/CS/7zip/Compress/LZ/LzBinTree.cs b/other-licenses/7zstub/src/CS/7zip/Compress/LZ/LzBinTree.cs new file mode 100644 index 000000000..7a9ca2092 --- /dev/null +++ b/other-licenses/7zstub/src/CS/7zip/Compress/LZ/LzBinTree.cs @@ -0,0 +1,367 @@ +// LzBinTree.cs
+
+using System;
+
+namespace SevenZip.Compression.LZ
+{
+ public class BinTree : InWindow, IMatchFinder
+ {
+ UInt32 _cyclicBufferPos;
+ UInt32 _cyclicBufferSize = 0;
+ UInt32 _matchMaxLen;
+
+ UInt32[] _son;
+ UInt32[] _hash;
+
+ UInt32 _cutValue = 0xFF;
+ UInt32 _hashMask;
+ UInt32 _hashSizeSum = 0;
+
+ bool HASH_ARRAY = true;
+
+ const UInt32 kHash2Size = 1 << 10;
+ const UInt32 kHash3Size = 1 << 16;
+ const UInt32 kBT2HashSize = 1 << 16;
+ const UInt32 kStartMaxLen = 1;
+ const UInt32 kHash3Offset = kHash2Size;
+ const UInt32 kEmptyHashValue = 0;
+ const UInt32 kMaxValForNormalize = ((UInt32)1 << 31) - 1;
+
+ UInt32 kNumHashDirectBytes = 0;
+ UInt32 kMinMatchCheck = 4;
+ UInt32 kFixHashSize = kHash2Size + kHash3Size;
+
+ public void SetType(int numHashBytes)
+ {
+ HASH_ARRAY = (numHashBytes > 2);
+ if (HASH_ARRAY)
+ {
+ kNumHashDirectBytes = 0;
+ kMinMatchCheck = 4;
+ kFixHashSize = kHash2Size + kHash3Size;
+ }
+ else
+ {
+ kNumHashDirectBytes = 2;
+ kMinMatchCheck = 2 + 1;
+ kFixHashSize = 0;
+ }
+ }
+
+ public new void SetStream(System.IO.Stream stream) { base.SetStream(stream); }
+ public new void ReleaseStream() { base.ReleaseStream(); }
+
+ public new void Init()
+ {
+ base.Init();
+ for (UInt32 i = 0; i < _hashSizeSum; i++)
+ _hash[i] = kEmptyHashValue;
+ _cyclicBufferPos = 0;
+ ReduceOffsets(-1);
+ }
+
+ public new void MovePos()
+ {
+ if (++_cyclicBufferPos >= _cyclicBufferSize)
+ _cyclicBufferPos = 0;
+ base.MovePos();
+ if (_pos == kMaxValForNormalize)
+ Normalize();
+ }
+
+ public new Byte GetIndexByte(Int32 index) { return base.GetIndexByte(index); }
+
+ public new UInt32 GetMatchLen(Int32 index, UInt32 distance, UInt32 limit)
+ { return base.GetMatchLen(index, distance, limit); }
+
+ public new UInt32 GetNumAvailableBytes() { return base.GetNumAvailableBytes(); }
+
+ public void Create(UInt32 historySize, UInt32 keepAddBufferBefore,
+ UInt32 matchMaxLen, UInt32 keepAddBufferAfter)
+ {
+ if (historySize > kMaxValForNormalize - 256)
+ throw new Exception();
+ _cutValue = 16 + (matchMaxLen >> 1);
+
+ UInt32 windowReservSize = (historySize + keepAddBufferBefore +
+ matchMaxLen + keepAddBufferAfter) / 2 + 256;
+
+ base.Create(historySize + keepAddBufferBefore, matchMaxLen + keepAddBufferAfter, windowReservSize);
+
+ _matchMaxLen = matchMaxLen;
+
+ UInt32 cyclicBufferSize = historySize + 1;
+ if (_cyclicBufferSize != cyclicBufferSize)
+ _son = new UInt32[(_cyclicBufferSize = cyclicBufferSize) * 2];
+
+ UInt32 hs = kBT2HashSize;
+
+ if (HASH_ARRAY)
+ {
+ hs = historySize - 1;
+ hs |= (hs >> 1);
+ hs |= (hs >> 2);
+ hs |= (hs >> 4);
+ hs |= (hs >> 8);
+ hs >>= 1;
+ hs |= 0xFFFF;
+ if (hs > (1 << 24))
+ hs >>= 1;
+ _hashMask = hs;
+ hs++;
+ hs += kFixHashSize;
+ }
+ if (hs != _hashSizeSum)
+ _hash = new UInt32[_hashSizeSum = hs];
+ }
+
+ public UInt32 GetMatches(UInt32[] distances)
+ {
+ UInt32 lenLimit;
+ if (_pos + _matchMaxLen <= _streamPos)
+ lenLimit = _matchMaxLen;
+ else
+ {
+ lenLimit = _streamPos - _pos;
+ if (lenLimit < kMinMatchCheck)
+ {
+ MovePos();
+ return 0;
+ }
+ }
+
+ UInt32 offset = 0;
+ UInt32 matchMinPos = (_pos > _cyclicBufferSize) ? (_pos - _cyclicBufferSize) : 0;
+ UInt32 cur = _bufferOffset + _pos;
+ UInt32 maxLen = kStartMaxLen; // to avoid items for len < hashSize;
+ UInt32 hashValue, hash2Value = 0, hash3Value = 0;
+
+ if (HASH_ARRAY)
+ {
+ UInt32 temp = CRC.Table[_bufferBase[cur]] ^ _bufferBase[cur + 1];
+ hash2Value = temp & (kHash2Size - 1);
+ temp ^= ((UInt32)(_bufferBase[cur + 2]) << 8);
+ hash3Value = temp & (kHash3Size - 1);
+ hashValue = (temp ^ (CRC.Table[_bufferBase[cur + 3]] << 5)) & _hashMask;
+ }
+ else
+ hashValue = _bufferBase[cur] ^ ((UInt32)(_bufferBase[cur + 1]) << 8);
+
+ UInt32 curMatch = _hash[kFixHashSize + hashValue];
+ if (HASH_ARRAY)
+ {
+ UInt32 curMatch2 = _hash[hash2Value];
+ UInt32 curMatch3 = _hash[kHash3Offset + hash3Value];
+ _hash[hash2Value] = _pos;
+ _hash[kHash3Offset + hash3Value] = _pos;
+ if (curMatch2 > matchMinPos)
+ if (_bufferBase[_bufferOffset + curMatch2] == _bufferBase[cur])
+ {
+ distances[offset++] = maxLen = 2;
+ distances[offset++] = _pos - curMatch2 - 1;
+ }
+ if (curMatch3 > matchMinPos)
+ if (_bufferBase[_bufferOffset + curMatch3] == _bufferBase[cur])
+ {
+ if (curMatch3 == curMatch2)
+ offset -= 2;
+ distances[offset++] = maxLen = 3;
+ distances[offset++] = _pos - curMatch3 - 1;
+ curMatch2 = curMatch3;
+ }
+ if (offset != 0 && curMatch2 == curMatch)
+ {
+ offset -= 2;
+ maxLen = kStartMaxLen;
+ }
+ }
+
+ _hash[kFixHashSize + hashValue] = _pos;
+
+ UInt32 ptr0 = (_cyclicBufferPos << 1) + 1;
+ UInt32 ptr1 = (_cyclicBufferPos << 1);
+
+ UInt32 len0, len1;
+ len0 = len1 = kNumHashDirectBytes;
+
+ if (kNumHashDirectBytes != 0)
+ {
+ if (curMatch > matchMinPos)
+ {
+ if (_bufferBase[_bufferOffset + curMatch + kNumHashDirectBytes] !=
+ _bufferBase[cur + kNumHashDirectBytes])
+ {
+ distances[offset++] = maxLen = kNumHashDirectBytes;
+ distances[offset++] = _pos - curMatch - 1;
+ }
+ }
+ }
+
+ UInt32 count = _cutValue;
+
+ while(true)
+ {
+ if(curMatch <= matchMinPos || count-- == 0)
+ {
+ _son[ptr0] = _son[ptr1] = kEmptyHashValue;
+ break;
+ }
+ UInt32 delta = _pos - curMatch;
+ UInt32 cyclicPos = ((delta <= _cyclicBufferPos) ?
+ (_cyclicBufferPos - delta) :
+ (_cyclicBufferPos - delta + _cyclicBufferSize)) << 1;
+
+ UInt32 pby1 = _bufferOffset + curMatch;
+ UInt32 len = Math.Min(len0, len1);
+ if (_bufferBase[pby1 + len] == _bufferBase[cur + len])
+ {
+ while(++len != lenLimit)
+ if (_bufferBase[pby1 + len] != _bufferBase[cur + len])
+ break;
+ if (maxLen < len)
+ {
+ distances[offset++] = maxLen = len;
+ distances[offset++] = delta - 1;
+ if (len == lenLimit)
+ {
+ _son[ptr1] = _son[cyclicPos];
+ _son[ptr0] = _son[cyclicPos + 1];
+ break;
+ }
+ }
+ }
+ if (_bufferBase[pby1 + len] < _bufferBase[cur + len])
+ {
+ _son[ptr1] = curMatch;
+ ptr1 = cyclicPos + 1;
+ curMatch = _son[ptr1];
+ len1 = len;
+ }
+ else
+ {
+ _son[ptr0] = curMatch;
+ ptr0 = cyclicPos;
+ curMatch = _son[ptr0];
+ len0 = len;
+ }
+ }
+ MovePos();
+ return offset;
+ }
+
+ public void Skip(UInt32 num)
+ {
+ do
+ {
+ UInt32 lenLimit;
+ if (_pos + _matchMaxLen <= _streamPos)
+ lenLimit = _matchMaxLen;
+ else
+ {
+ lenLimit = _streamPos - _pos;
+ if (lenLimit < kMinMatchCheck)
+ {
+ MovePos();
+ continue;
+ }
+ }
+
+ UInt32 matchMinPos = (_pos > _cyclicBufferSize) ? (_pos - _cyclicBufferSize) : 0;
+ UInt32 cur = _bufferOffset + _pos;
+
+ UInt32 hashValue;
+
+ if (HASH_ARRAY)
+ {
+ UInt32 temp = CRC.Table[_bufferBase[cur]] ^ _bufferBase[cur + 1];
+ UInt32 hash2Value = temp & (kHash2Size - 1);
+ _hash[hash2Value] = _pos;
+ temp ^= ((UInt32)(_bufferBase[cur + 2]) << 8);
+ UInt32 hash3Value = temp & (kHash3Size - 1);
+ _hash[kHash3Offset + hash3Value] = _pos;
+ hashValue = (temp ^ (CRC.Table[_bufferBase[cur + 3]] << 5)) & _hashMask;
+ }
+ else
+ hashValue = _bufferBase[cur] ^ ((UInt32)(_bufferBase[cur + 1]) << 8);
+
+ UInt32 curMatch = _hash[kFixHashSize + hashValue];
+ _hash[kFixHashSize + hashValue] = _pos;
+
+ UInt32 ptr0 = (_cyclicBufferPos << 1) + 1;
+ UInt32 ptr1 = (_cyclicBufferPos << 1);
+
+ UInt32 len0, len1;
+ len0 = len1 = kNumHashDirectBytes;
+
+ UInt32 count = _cutValue;
+ while (true)
+ {
+ if (curMatch <= matchMinPos || count-- == 0)
+ {
+ _son[ptr0] = _son[ptr1] = kEmptyHashValue;
+ break;
+ }
+
+ UInt32 delta = _pos - curMatch;
+ UInt32 cyclicPos = ((delta <= _cyclicBufferPos) ?
+ (_cyclicBufferPos - delta) :
+ (_cyclicBufferPos - delta + _cyclicBufferSize)) << 1;
+
+ UInt32 pby1 = _bufferOffset + curMatch;
+ UInt32 len = Math.Min(len0, len1);
+ if (_bufferBase[pby1 + len] == _bufferBase[cur + len])
+ {
+ while (++len != lenLimit)
+ if (_bufferBase[pby1 + len] != _bufferBase[cur + len])
+ break;
+ if (len == lenLimit)
+ {
+ _son[ptr1] = _son[cyclicPos];
+ _son[ptr0] = _son[cyclicPos + 1];
+ break;
+ }
+ }
+ if (_bufferBase[pby1 + len] < _bufferBase[cur + len])
+ {
+ _son[ptr1] = curMatch;
+ ptr1 = cyclicPos + 1;
+ curMatch = _son[ptr1];
+ len1 = len;
+ }
+ else
+ {
+ _son[ptr0] = curMatch;
+ ptr0 = cyclicPos;
+ curMatch = _son[ptr0];
+ len0 = len;
+ }
+ }
+ MovePos();
+ }
+ while (--num != 0);
+ }
+
+ void NormalizeLinks(UInt32[] items, UInt32 numItems, UInt32 subValue)
+ {
+ for (UInt32 i = 0; i < numItems; i++)
+ {
+ UInt32 value = items[i];
+ if (value <= subValue)
+ value = kEmptyHashValue;
+ else
+ value -= subValue;
+ items[i] = value;
+ }
+ }
+
+ void Normalize()
+ {
+ UInt32 subValue = _pos - _cyclicBufferSize;
+ NormalizeLinks(_son, _cyclicBufferSize * 2, subValue);
+ NormalizeLinks(_hash, _hashSizeSum, subValue);
+ ReduceOffsets((Int32)subValue);
+ }
+
+ public void SetCutValue(UInt32 cutValue) { _cutValue = cutValue; }
+ }
+}
|